One alternative implementation of this which is very simple is as follows.<p>1. User makes a public declaration to always make a prediction using some platform. Like they release a tweet saying all future predictions will happen on futuu.re (or on a Blockchain)<p>2. They only release the sha hashes of their prediction to futuu.re, along with a date for that prediction, and users keep the true prediction with themselves. At any time before deadline they must reveal the content to the world and tell futuu.re about it. Futuu.re verifies that the sha matches the prediction and keeps an easy record. All predictions must start with a preamble.<p>3. futuu.re maintains three counters for a use, one showing the number of predictions made till that time, second showing predictions that should be revealed till that time, third showing the number of predictions that have been revealed . This establishes the long time accuracy of the user.<p>This way when someone reveals their pok then the public will know whether they tried to fool people because the users trust ratio will go down if they make a lot of predictions without revealing them. This is also more secure since the actual content is never stored on the server.<p>The only thing that needs to be done is to use a content formatter/validator at the time of hash creation for stylstic reasons and to make it convenient for public to verify the accuracy of the user.